To view the ink percentage at any point on the layout:
1 Position the mouse where you want to evaluate the ink percentages.
2 Refer to the percentages along the right side of the Separations Preview palette. Ink values for each plate are displayed, along with the total for CMYK plates only.
Note: When you view ink limits for a document that contains both process and spot colors, determine the total ink percentage by adding the CMYK ink percentage to the percentages of each spot color.
To change how single plates display:
On the Separations Preview palette menu, select Show Single Plates as Black to display plates as black when displayed alone, or deselect it to display plates in their actual ink color.
To change how black displays:
On the Separations Preview palette menu, select Desaturate Black to display actual rich black opacity (opacity as combined with other inks), or deselect Desaturate Black to display black as
100% opaque.
Overprint Preview
Overprint Preview is a View menu command that simulates how objects that use the Overprint attribute will appear in color-separated output (or composite output when the Simulate Overprint option is enabled). Overprint Preview is exactly the same as using the Separations Preview palette with all inks displayed, so you can use it as a shortcut for that specific view. When
Overprint Preview is on, you can see underlying objects through overprinted objects as they would appear on press. Because Overprint Preview models ink behavior, overprinted objects that use lighter or screened inks reveal more underlying inks during overprint preview because they actually are less opaque when printed.
Overprint Preview off (left) and on (right), where the text fill and stroke and the wave’s light blue stroke are all set to overprint in the Attributes palette. Because strokes are centered above fill edges, half of each stroke falls outside each fill.
When using Overprint Preview, use the same guidelines listed for the Separations Preview palette on page 54.
To preview overprinting:
Choose View > Overprint Preview.
Note: You can also preview overprints when you output to a composite printing device or PDF file. To do this, turn on Simulate Overprint in the Advanced panel of the Print dialog box or the Export PDF dialog box. Simulate Overprint should be off when creating actual separated output—as its name indicates, this feature is intended for proofing only, and won’t preserve spot colors.
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Flattening transparency for high-resolution output
Transparency has been a feature of image editors such as Adobe Photoshop for many years.
The design advantages of transparency are so compelling that customers have long requested a similar capability in vector drawing and page layout programs. While some drawing programs support transparency for a limited range of objects, Adobe supports transparency at a fundamental level so that it can be used for any practical application, from true semitransparent drop shadows to changing the opacity of any object. To make this happen, Adobe includes support for transparency in the Adobe Graphics Manager (AGM) graphics engine to provide high-quality display of transparency effects. Integrated support for transparency enables transparency effects to be preserved from Illustrator and Photoshop files and applied to InDesign objects.
Native transparency or live transparency are terms for the data that describe transparency, such as specifying 25% opacity or a Screen blend mode. However, Adobe PostScript thinks in terms of solid or screened color and grayscale values, with no support for native transparency data.
For this reason, native transparency must be flattened—converted to the ink values required to reproduce the appearance of transparency on press. Flattening can be done by a RIP or by the application generating output data. RIPs are available that can process native transparency data directly, by supporting PDF 1.4 and flattening transparency data in-RIP. But many RIPs in use today can’t process transparency data directly, so before sending them to such a device, documents that use transparency must be flattened in advance.
It may seem that transparency creates a special case for a service provider to handle. However, this situation continues to improve with time. Transparency is already part of the PDF 1.4 and
1.5 specifications supported by Adobe InDesign (starting from version 2), Acrobat (starting from version 5), and Illustrator (starting from version 9). And as noted above, RIPs are available that can receive native transparency. As device manufacturers and service providers upgrade RIPs, software, and workflows, flattening in advance becomes less necessary. Adobe’s goal is to make working with native transparency as routine as it is to work with line screens today (which were a challenge in the early days of desktop publishing).
For devices that don’t yet have the ability to process native transparency, Adobe InDesign includes tools that help you efficiently prepare transparency for high-quality output. The Flattener Preview palette works together with transparency flattener presets so that you can evaluate, customize, and apply them. Also, the Pages palette indicates the spreads on which transparency
(from Adobe Illustrator 9 and up; InDesign, or Photoshop) is used, by displaying those pages with a checkerboard pattern.
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